HYPOTHEIS & TYPES OF VARIABLES

Prepared By : SONDARVA YAGNESH M.sc.(Agri) Extension 1st semester BACA, AAU, Anand

Hypothesis

Webster: “ Hypothesis is a proposition or condition or principle which is assumed in order to draw out its logical consequences and by this method, to test its accord with facts which are known or may be determined.”

Lundberg: “Hypothesis is a hunch, guess or imaginative idea which becomes the basis for action or investigation.”

Hypothesis

Kerlinger: “Hypothesis is a conjectural statement of the relation between two or more variables.”

Black: “ Hypothesis is a proposition not known to be definitely true or false, examined for the sake of determining the consequences which would follow from its truth.”

Theory and Hypothesis

Theory is used to denote a hypothesis that is almost completely established and well on the way towards becoming a law.

According to Webster: “A hypothesis is a propositional conjecture as to causes or relations of phenomenon, while a theory is a verified hypothesis applicable to many related phenomenon.”

Thus, scientific march of a hypothesis leads towards theory.

Characteristics of a good hypothesis

Clear, specific and limited in scope Simply stated Consistent with the relevant objectives of

research Capable of being tested and related to

available techniques Not include value judgments, relative terms

or any moral teaching State the relationship between variables, if

the study is designed for that

Sources of hypothesis

Experience of researcher Review of literature Findings of the pilot study Interaction with knowledgeable persons of

the concerned field Knowledge of culture and society Creative thinking and imagination of

researcher

Utility of hypothesis

It acts as a guide- a sort of guiding light in the journey of research.

It prevents blind research. It spells out the difference between fruitful and fruitless research.

It provides direction to research, identifying what is relevant and what is irrelevant.

It serves as a framework for drawing meaningful conclusions.

Types of hypothesis

Null Hypothesis (Ho): It is the hypothesis which is set for possible

rejection under the assumption that it is true. It is the hypothesis of no difference. It states that there is no difference between the population under study.It is like the legal principle that a person is innocent until proved guilty. It constitute a challenge and the function of a researcher is to give the facts a chance to refute this challenge.

Ho : The males and females do not differ significantly in respect of their frequency of televiewing.

Alternative Hypothesis (H1)It is one which is set for possible acceptance or possible inequality. It is a complementary statement to the null hypothesis. It is very important to state the alternative hypothesis explicitly, because rejection of null hypothesis implies acceptance of alternative hypothesis and vice-versa.

H1 :The females watch television significantly more than the males

Level of significance

Since no one is ever certain that the sample information accurately represents the population information, researchers specify the risk of rejecting the null hypothesis when it is correct. This risk, expressed in terms of probability, is called the level of significance.

Two levels of significance are commonly used: 0.05 or 5% 0.01 or 1 %

Type I and Type II errors

Test of significance is the test of correctness of hypothesis on the basis of information obtained from the sample.

In testing the null hypothesis, we may come across the following alternatives:

1. Ho is correct, test accepts Ho2. Ho is not correct, test rejects Ho3. Ho is correct, but test rejects Ho (Type I error)4. Ho is not correct, but test accepts Ho (Type II error)

VARIABLE

A variable is a characteristic of interest that varies from one item to another and may take any one of a specified set of values or attributes.

It can be defined as any characteristic of an individual or a thing under study.

In other words, it means some characteristics of each number of the unit that is to be studied such as income, age, test score, land holding, etc.

Any item or characteristic which can be observed or measured and whose observation or measurement will be useful for the study can be regarded as a variable for the study.

A variable can take on different values for different individuals Ex: Heights of individuals: Student #1: 5’ 5” Student #2:

5’ 7” Student #3: 5’ 2”

Types of variables

Variables

Discrete Continuous

Dichotomous Polytomous

Dependant Independent

Intervening

Stimulus ResponseQualitative

Active

Quantitative

Types of variables

Quantitative variable:It is one which generates numerical values.For example, consider a study of guests at a hotel. We may be interested in the age of a guest, their spend and length of stay. Each characteristic is a quantitative variable because the data that each generates is numerical – for instance, a guest may be 34 years of age, spend Rs.500 and stay for seven days. Quantitative variables generate quantitative data.

Types of variables

Qualitative variable:Any variable that cannot be manipulated or at least is difficult to manipulate is called qualitative variable. Qualitative variables generate non-numerical or qualitative data. For instance, ‘nationality of hotel guest’ is a qualitative variable because nationality can be classified as British, American, French, etc.

Active variable:A variable that is manipulated is called active variable. e.g. creating anxiety through agricultural film show, award of prizes etc.

Types of variables

Discrete variable:It is the one which involves counting the number of events. It consists of only whole numbers; fractional values can’t occur.e.g. the number of inhabitants in a village

Continuous variable:They are divisible into smaller and smaller fractional units. e.g. age of farmer. The characteristic of a continuous variable is that , within whatever limits its values may range, any value is possible.

Types of variables

Dichotomous variable:A variable which has only two values.e.g. female-male, adopter-non-adopter

Polytomous variable:It can have more than two values.e. g. the influencing skill of extension worker may be high, some what high, medium, low etc.

Classification of variables

Independent – This variable is the presumed cause of the dependent variables Dependent – This variable is the presumed effect / consequences .It is the condition

which the researcher tries to explain.

Effect / consequences

Education Adoption (independent variables) (dependent variable)

Types of variables

Intervening variable: According to Kerlinger, “ the constructs,

which are non-observable, are called intervening variables.” It can neither be seen, nor heard nor felt. It is inferred from the behavior. e.g. Hostility is inferred from hostile or aggressive acts. Motivation can be inferred from motivated behavior.

Types of variables

Stimulus variable:It is the condition or manipulation created by the researcher so as to evoke a response in an organism. The general class of things that relate to the environment, situation or condition of stimulation are referred to as stimulus variables. e.g. a slide show, a field day, method demonstration etc.

Types of variables

Response variable:Any kind of behavior of the respondent is called response or behavioral variable. This refers to some action or response of an individual. It may also refer to the frequency with which a particular event occurs or it may be the scale value of a particular event. e.g. the response of farmers for questions like, have you attended the field day? Yes/No.

Types of variables

Extraneous variable:Extraneous variables are those variables that are not related to the purpose of the study, but may affect the dependent variable. It is therefore essential that extraneous variables are controlled. For example, intelligence may be the extraneous variable in studying the efficacy of method of instruction on the achievement score.